De-Catted 2011 Road Glide Ultra
Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
Likes: 224
From: Glendale AZ
This whole cross talk between O2 sensors still doesn't make sense to me. With the Cat installed both O2 sensors are before the catalyst and one O2 sensor sits in the protected area of the front pipe. So why are the exhaust gases any different if both the sensors are before the CAT either installed or removed? I'm not sure how this theory is either proven or dis proven other than someone saying it's a fact. What facts back up their claim other than he is a well known tuner? I'm just wanting to get my facts straight and don't want to hurt my motor over the price of a $450 head pipe. The bike seems to run fine.
Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
Likes: 224
From: Glendale AZ
I call foul on the o2 sensor crosstalk debate.
Those of you that have cut the pipe open with a hatch style cut - for lack of better word - know that the converter material starts about 1" after the first weld, and that the o2 sensors are located 3" before the weld. So that already makes at least a 4" void that exhaust gasses can already hang out in.
Basically what Im sayin if you look at the picture (courtesy JCturbo and his thread) you will see a void already exists, and there is no way that crosstalk doesnt already happen.
**** while were at it, aren't we saying basically that the rear head is the one getting messed up, cause its the one that not "separate"? Hmm maybe the moco already knows about the crosstalk and the lean condition, and that is why they installed the engine temp management system?
Come on guys put two and two together....
I did mine 1000 miles ago, I have not one problem....
Those of you that have cut the pipe open with a hatch style cut - for lack of better word - know that the converter material starts about 1" after the first weld, and that the o2 sensors are located 3" before the weld. So that already makes at least a 4" void that exhaust gasses can already hang out in.
Basically what Im sayin if you look at the picture (courtesy JCturbo and his thread) you will see a void already exists, and there is no way that crosstalk doesnt already happen.
**** while were at it, aren't we saying basically that the rear head is the one getting messed up, cause its the one that not "separate"? Hmm maybe the moco already knows about the crosstalk and the lean condition, and that is why they installed the engine temp management system?
Come on guys put two and two together....
I did mine 1000 miles ago, I have not one problem....
Advanced
Joined: Mar 2009
Posts: 73
Likes: 0
From: Orleans Ontario Canada
I ended up re installing my stock header. My reserve mileage was up by too much , to me this was an indication of a leaner mix. With the stock slip on the mileage went down some, I figure less reversion with stock. I took a picture of the 2 headers side by side and the rear is alot bluer and dark and the front a little bluer. On another forum a tech with dyno noted that when he let the bike run in closed loop ,the longer it ran the leaner the rear cylinder got. That was what was happening to me. Even with FL vied 10 it did not matter. If the sensors are not reading right the xied are only getting the wrong signal.
I may be in left field, these are just my opinons. Until I do a proper set up I will stay with the stock header.
I may be in left field, these are just my opinons. Until I do a proper set up I will stay with the stock header.
Extreme HDF Member
Joined: Dec 2007
Posts: 13,402
Likes: 941
From: Illinois
De-catting has no effect on the running what so ever. Many have done in from 10 on. The HD cat is very high flow and does not change the amount of back pressure or anything.
A HD ECM can and will adjust for both a high flow intake and exhaust. The change is back to 14.7 to 1 AFR to keep the bike emissions compliant. But that is not what you want.
I ran mine for 8K before I even put a tuner in it (Fi2000r).
A HD ECM can and will adjust for both a high flow intake and exhaust. The change is back to 14.7 to 1 AFR to keep the bike emissions compliant. But that is not what you want.
I ran mine for 8K before I even put a tuner in it (Fi2000r).
Extreme HDF Member
Joined: Dec 2007
Posts: 13,402
Likes: 941
From: Illinois
Doc's Performance doesn't know ****. If you search hard enough you will find HD's own information that adding a breather and exhaust will only cause the EMC to adjust AFR back to 14.7 to one.
This information was starting with 06 and continues to date.
Again gutting the cat does not affect starting, running or any other issue.
But no one wants to run the 14.7 to one AFR. That is the reason for a tune.
Note: Few understand that the SE set of tunes also does NOT change the 14.7 to 1 AFR. Why? You ask. Because HD would be fined $10,000 per unit that they changed by EPA. It is against the law for them to mess with changing the AFR. This is another matter that if you research HD material you will find HD acknowledging this fact.
So go to after market tuners to get your money's worth.
This information was starting with 06 and continues to date.
Again gutting the cat does not affect starting, running or any other issue.
But no one wants to run the 14.7 to one AFR. That is the reason for a tune.
Note: Few understand that the SE set of tunes also does NOT change the 14.7 to 1 AFR. Why? You ask. Because HD would be fined $10,000 per unit that they changed by EPA. It is against the law for them to mess with changing the AFR. This is another matter that if you research HD material you will find HD acknowledging this fact.
So go to after market tuners to get your money's worth.
Cruiser
Joined: Sep 2011
Posts: 116
Likes: 2
From: Howell MI
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Road Warrior
Joined: Jul 2010
Posts: 1,816
Likes: 2
From: New Hampshire
De-catting has no effect on the running what so ever. Many have done in from 10 on. The HD cat is very high flow and does not change the amount of back pressure or anything.
A HD ECM can and will adjust for both a high flow intake and exhaust. The change is back to 14.7 to 1 AFR to keep the bike emissions compliant. But that is not what you want.
I ran mine for 8K before I even put a tuner in it (Fi2000r).
A HD ECM can and will adjust for both a high flow intake and exhaust. The change is back to 14.7 to 1 AFR to keep the bike emissions compliant. But that is not what you want.
I ran mine for 8K before I even put a tuner in it (Fi2000r).
I know when I put on the Ness Big Sucker as few weeks back that the bike started to run pretty lean...leaner than stock...head pipe was always a sort of golden color before the Big Sucker but it sure heated up and pipes turned a nice purple and blue after the Hi Flow A/C went on (no tuner)
Cruiser
Joined: Oct 2008
Posts: 110
Likes: 0
From: FL
I'm with YOU man...upgrades are in my sig but I haven't had any issue...over 1500 miles since I gutted the pipes too